Grinding-machine.



J. A. HUNTER.

GRINDING MACHINE.

APPLICATION FILED 110V. 3, 1911.

1 633133 11 Patented July 9,1912.

ITNESSES W LVLYMB v 40., dent to leaks.

atom: a. H'onrnn, or onnvEnann, OHIO.

GRINDING-MACHINE.

Specification of Letters Patent.

Patented arra s, m2.

Application filed November 3, 19 11. Serial Ito 558,323.

,5 State of Ohio, have invented certainnew and useful Improvements in Grinding- Machines, of which the following is a specilication.

This invention relates to grinding ma- 19 chines, and although it may be used for other purposes, it 1s particularly intended for use to grind off the top of 'digesters used in garbage reduction plants. These digesters are large cast iron receptacles in- 5 which garbage and fats are reduced by boilang in order to obtain desired products. These receptacles are quite large and heavy, having walls from two and a half to four inches thick and standing about eighteen 20 feet high. In the use thereof, a cap is applied to the top or mouth, and the edge to which the cap is applied becomeseroded, from the strong fumes and gases, to such an extent as to make it almost impossible to keep the digester air tight, even with gaskets now used for that purpose, -as the gaskets quickly become worn and give way before the high pressure." The machine forming the subject of the present invention may be used to grind off the top of these digesters, making the use of gaskets almost unnecessary, and if they are used they rest upon a smooth and level edge, and can not blow out. A tightfitting cover is essential to prevent the escape of obnoxious gases and soluble products, thereby increasing the output of the plant and improving atmospheric conditions around the same, and gener ally avoiding trouble inci- The machine is illustrated in the accompanying drawings in which Figure 1 is a vertical sect1on-of the same showing the manner of its application to the neck of a digester. Fig. 2 is a top plan electric-motor, the shaft of which carries an emery or other grinding wheel 7 The motor is fastened to a base'20 which rests on a turntable 8. The base plate 20 is slotted as shown at 21 and is attached to the turntable by a bolt 22 extending through the slot, with a washer 23 under the head of the bolt. .The bolt holds the base plate in position, but said plate can nevertheless be adjusted, at least by loosening the bolt a trifle, by" means of a screw 15 which works through a fixed nut 24 on the turntable and turns in a post or stud 25 on the base plate. By manipulating the screw the base plate is carriedback and forth as desired. The turntable has at the center a depending hub 25 which fits at a working fit in a sleeve bearing or thimble 11 The thimble has at the top a flange 11' on which the turntable rests, and the parts are held together by a central bolt 10. The flange 11 has openings 17 to receive a spanner. The thimble is exteriorly threaded, and screws into a supporting frame or platform 13, .where it may be locked by a lock nut 12 screwed on the thimble. By loosening the lock nut the thimble may be raised or lowered to adjust the grinder vertically, in order to properly position the wheel 7 with respect to the work. The supporting platform is held in I position in the neck of the digester by means of pointed screws 14 which may be advanced radially into the wall of theneck to fasten the platform in place. The platform is recessed as shown at 30 to allow a wrench to be applied'to the screws. I

In the use of the device, the platform 13 is first lowered into theneck of the digester, and the screws 14 advanced to fasten the same in place. The thimble 11 is then screwed into the platform with the turnraised or lowered until. the grinding disk 7 is inproper position with respect to the work. Then the lock nut 12 is tightened.

The motor is then started and the grinding wheel rotates in contact, with the edge of the digester. The turntable may be turned to carry the wheel around the whole circum' ference of the digester neck, this being conveniently done by means of a handle 31 attached to the turntable. To cover the complete width of the digester wall the plate 20 carrying the motor and grinding wheel may be shifted in and out by turning the screw 15. If necessary after one setting, the grindingwheel can be lowered again by loosening the lock nut 12 and screwing down the thimble 11. After a flat surface has been ground on the digester, a groove of any plate 20,'to receive packing if necessary.

'table in position, and by the use of a spanner Wrench in the holes 17 the thimble 1s size can be ground, by proper setting of the the ends of any The device is c apable of use for grinding circular article. 7

,An important advantage of the machine is its simplicity of; Construction and opera tion, the services of aslgilled mechanic be ing unnecessary. The adjusting and'oper ating devices are all easy of-access, and the whole; forms a very rigid and compact machine, well adapted for the intended pur pose. The central support for the turntable is-strong and rigid, avoiding vibrations, or the necessity for a counterbalance for the motor. 1

I claim:

41. The combination of a platform, means.

to fasten the-same to an annular piece '-of work and within the same, a turntablQ platform adjustable to raise or lower the cylindrical or other hollow V tsijeaa' "hm-e13 g'i'gr'l'mdiilg wheel iimmaei on th turntableto revolve therewith, and means to rotate'the grinding wheel;

. 3. The combination of a platform, means at" the outer edge thereof engagable with H the inner surface of an annular piece of work to support the platform within'saide piece of'work, a turntable mounted to re-.

volve onthe platform, a radially. adjustable grinding wheel carriedby the turntableandgrinding wheel,

thimble, a grinding Wheelcarried by the turntable and revoluble therewith, and meansto-rotate the ,wheela 1 s5 1 'revoluble therewith, and means to rotate the 4. The combination of a platform, a bearing thimble adjustably screwed. into the same, a turntable having a hub fitting in the 40 I In testimony whereof,,][ do afix mysignature 'in'presence of two witnesses.

enn A; HUNTER. Witnesses: i' CLAR NJWHITFIELD,

' STEIJMAN J. ROCKWELL. 

